1. Field of the Invention
The present invention generally relates to a heat sink for removing heat from a heat generating component, and in particular to a heat sink suitable for automated production with reduced costs.
2. The Prior Art
Electronic devices or components, such as a central processing unit of a computer, which generate heat during operation require a heat removing device such as a heat sink in order to maintain a proper operational temperature. Several different types of heat sinks available such as those disclosed in U.S. Pat. Nos. 4,884,331 and 5,038,858 and Taiwan Patent Application No. 85212486 which are respectively shown in FIGS. 1, 2 and 3 of the attached drawings.
In FIG. 1, a heat sink 60 made by aluminum extrusion is shown. The heat sink 60 requires sawing and surface finishing to obtain the final product, which is a tedious and laborious process. Furthermore, the ratio of the height h of the fins to the distance d between adjacent fins is limited to a maximum value of 13:1. Thus, improvement of the heat removal rate of the heat sink is limited.
A heat sink 70 comprising a base 74 defining a plurality of grooves 76 for receiving and retaining fins 72 therein is shown in FIG. 2. The heat sink 70 overcomes the problems encountered by the heat sink 60 illustrated in FIG. 1, but the heat removal rate is adversely affected by gaps 78 inevitably existing between the fins 72 and the base 74.
FIG. 3 shows a folded-fin heat sink 80 constructed by folding a thin conductive plate to form a number of spaced fin panels joined by connecting sections 82. The connecting sections 82 are positioned to physically contact a base 84. Due to manufacturing tolerances, gaps often exist between the connecting sections 82 and the base 84 thereby creating a heat transfer barrier and minimizing the heat removal efficiency of the heat sink 80.
It is thus desirable to have a heat sink which overcomes the disadvantages associated with the conventional heat sinks.